US congress rejects the Bush bailout plan. I'm shocked and pleased.
Now unemployed, Ehud Olmert finally talks some sense: suggests full Israeli withdrawal from West Bank and East Jerusalem.
Palin is starting to smell too much like moron even for Republicans. Looking forward to seeing her in tomorrow's debate with Joe Biden.
30 September 2008
26 September 2008
25 September 2008
20 September 2008
12 September 2008
11 September 2008
09 September 2008
08 September 2008
Synchronized
Robert Desimone - Neural Synchrony and Selective Attention (54 min, iTunes U)
In this lecture Desimone describes his work on the relation between neural synchrony and attention (awareness). Like animals, neurons have to produce limited but useful (axonal-) output from an enormous quantity of (dendritic-) input. Neurons respond most strongly when this input is synchronized, thanks to cumulative excitation I guess.
Desimone has been recording from all over monkey cortex during attention tasks and finds synchronized activity in neurons that process visual information that animals have been trained (juice reward..) to attend to. Importantly, he notes that this synchrony begins DOWNSTREAM, in frontal cortex, and propagates BACKWARDS to early visual cortex, where cells have smaller receptive fields (and do not receive dopamine from that juice reward..). Very interesting. Desimone focuses primarily on synchrony in the gamma oscillations of the outer cortical layers, I'm not sure what kind of activity those oscillations refer to, probably local field potentials but what's the spatial resolution?
In this lecture Desimone describes his work on the relation between neural synchrony and attention (awareness). Like animals, neurons have to produce limited but useful (axonal-) output from an enormous quantity of (dendritic-) input. Neurons respond most strongly when this input is synchronized, thanks to cumulative excitation I guess.
Desimone has been recording from all over monkey cortex during attention tasks and finds synchronized activity in neurons that process visual information that animals have been trained (juice reward..) to attend to. Importantly, he notes that this synchrony begins DOWNSTREAM, in frontal cortex, and propagates BACKWARDS to early visual cortex, where cells have smaller receptive fields (and do not receive dopamine from that juice reward..). Very interesting. Desimone focuses primarily on synchrony in the gamma oscillations of the outer cortical layers, I'm not sure what kind of activity those oscillations refer to, probably local field potentials but what's the spatial resolution?
06 September 2008
05 September 2008
04 September 2008
Bill Maher is back :)
Whoooo! Bill Maher is back! He may be a backwards leftie about medicine but political analysis doesn't get more entertaining than this.
03 September 2008
02 September 2008
Work in progress
The iPlant is all good and well but endogenous - natural - activation of midbrain dopamine (DA) neurons is just as important. DA neurons, whose function is strengthening of active cell assemblies in the frontal cortex ('attention'), generation of motivation ('desire'), and facilitation of declarative learning in the hippocampus and procedural learning in the striatum, are naturally activated by many nerve bundles, including glutamatergic (Glu) projections from sensory and frontal cortex. Of these two, the frontal cortex is more important, because it receives more DA and expresses more DA receptors, and therefore forms, with these DA neurons, an enormously adaptive and tightly knit circuit that we call 'I'.
In the addictive personality (ADHD humans, SH rats) the ability of the frontal cortex to activate and be activated by midbrain DA neurons is low, making the individual unusually reliant on sensory and other ways of activating midbrain DA neurons. Although a slim circuit and its steep delay of reinforcement gradient ('high impulsivity') may have been adaptive during evolution it can be a profound nuisance in a post-industrial environment that generally rewards long-term thinking and self-discipline. Recieving relatively little dopamine, the frontal cortex of the addictive personality becomes hypersensitive to the transmitter and will gravitate towards environmental and chemical stimulants.
In the addictive personality (ADHD humans, SH rats) the ability of the frontal cortex to activate and be activated by midbrain DA neurons is low, making the individual unusually reliant on sensory and other ways of activating midbrain DA neurons. Although a slim circuit and its steep delay of reinforcement gradient ('high impulsivity') may have been adaptive during evolution it can be a profound nuisance in a post-industrial environment that generally rewards long-term thinking and self-discipline. Recieving relatively little dopamine, the frontal cortex of the addictive personality becomes hypersensitive to the transmitter and will gravitate towards environmental and chemical stimulants.
Transplant
C: i've got a question
L: yea?
C: we're able to, indeed encouraged to, donate organs. when it's possible to donate bits of the nervous system, what will people say? will we donate on not?
L: live donation or after death?
C: like donate your visual cortex to someone who lost sth in trauma. if your heart's about to go out or sth
not many deaths are CNS
L: thats the thing. brain doesnt stay fresh very long. it wouldnt be feasible for accidents and such. only if you're like: okay, lets turn of the machines now
C: no but for people dying in hospital bed
yea
L: i can imagine a lot of ppl having issues w that. personality and such
C: could you donate a whole brain? it might be easier actually ;)
of course
L: likely (the easier bit, not the could you bit)
i guess you could start w donating spinal cord. thats fairly unpersonal
C: or adrenal gland.
L: move up from there
yea
thats not nervous system tho
C: no?
L: ppl get thyroids implanted, no?
C: is to me
L: noooo
C: don't kno
L: its connected
but endocrine system, strictly speaking
C: is sex steroids and cortisol and all them tho!
L: yea yea. neuroendrocinology is a beautiful thing. a lot of those hormones are systemic in nature tho. bottom up control of brain, not nervous system, at least certainly not cns
i wonder if you could graft a piece of visual cortex into someone else's brain
connections and stuff
C: or frontal..
L: better than going blind maybe, but prob v difficult
or that..
L: yea?
C: we're able to, indeed encouraged to, donate organs. when it's possible to donate bits of the nervous system, what will people say? will we donate on not?
L: live donation or after death?
C: like donate your visual cortex to someone who lost sth in trauma. if your heart's about to go out or sth
not many deaths are CNS
L: thats the thing. brain doesnt stay fresh very long. it wouldnt be feasible for accidents and such. only if you're like: okay, lets turn of the machines now
C: no but for people dying in hospital bed
yea
L: i can imagine a lot of ppl having issues w that. personality and such
C: could you donate a whole brain? it might be easier actually ;)
of course
L: likely (the easier bit, not the could you bit)
i guess you could start w donating spinal cord. thats fairly unpersonal
C: or adrenal gland.
L: move up from there
yea
thats not nervous system tho
C: no?
L: ppl get thyroids implanted, no?
C: is to me
L: noooo
C: don't kno
L: its connected
but endocrine system, strictly speaking
C: is sex steroids and cortisol and all them tho!
L: yea yea. neuroendrocinology is a beautiful thing. a lot of those hormones are systemic in nature tho. bottom up control of brain, not nervous system, at least certainly not cns
i wonder if you could graft a piece of visual cortex into someone else's brain
connections and stuff
C: or frontal..
L: better than going blind maybe, but prob v difficult
or that..
01 September 2008
Morons
Aaa, how cute. Let's have a debate entitled 'Battle of Ideas' about the moral and legal implications of neuroscience, and let's have the panel consist of four white, middle-aged men who all agree, from the start, that neuroscience has no impact on notions of responsibility.
Don't get me wrong, I'm not saying the panelists are morons, the sociologist at the end has an interesting thing or two to say and Pierre Magistretti made good contributions to a MUCH better discussion over at the incomparable Philoctetes Center. I'm saying whoever arranged this supposed Battle showed a moronic lack of imagination.
Don't get me wrong, I'm not saying the panelists are morons, the sociologist at the end has an interesting thing or two to say and Pierre Magistretti made good contributions to a MUCH better discussion over at the incomparable Philoctetes Center. I'm saying whoever arranged this supposed Battle showed a moronic lack of imagination.
Neurodegeneration
Last week brain developed a highly dopaminergic pathway regarding neurodegenration (read: 'Last week I found a very good reason to take a serious interest in dementia'). Only 2% of people aged 65-75 suffer dementia, but as the babyboomer generation gets older and medical science continues to develop cures for everything BUT neurodegeneration, diseases like Alzheimer's (50% of dementias) and vascular dementia (30%) will become some of the largest strains on European, north American, East Asian and Australian economies over the next few decades. Paying pensions will be difficult and the cost of physical and psychological care for boomers with dementia will outweigh TOTAL current spending on healthcare.
So. It turns out the best form of preventative treatment for neurodegenerative diseases is physical exercise. For details on this I strongly recommend a 35 min audio clip by John Medina called 'Brain Rule 1: Exercise', which is available on iTunes and explains in a clear, no-neuroscience-knowledge-needed way how increased blood and oxygen supply stimulates neurogenesis and helps fight the buildup of free radicals.
Very few people exercise properly, hence the obesity epidemic. Some of the aforementioned nations may therefore be open to alternative ways of avoiding disaster, say a brain implant that helps people exercise.. I'm sure you see where I'm going with this.
So, my apologies in advance to those of you who know a lot more than me about this subject - please correct me when I over-simplify and feel very free to point me to new sources of information, particularly audiovisual ones.
So. It turns out the best form of preventative treatment for neurodegenerative diseases is physical exercise. For details on this I strongly recommend a 35 min audio clip by John Medina called 'Brain Rule 1: Exercise', which is available on iTunes and explains in a clear, no-neuroscience-knowledge-needed way how increased blood and oxygen supply stimulates neurogenesis and helps fight the buildup of free radicals.
Very few people exercise properly, hence the obesity epidemic. Some of the aforementioned nations may therefore be open to alternative ways of avoiding disaster, say a brain implant that helps people exercise.. I'm sure you see where I'm going with this.
So, my apologies in advance to those of you who know a lot more than me about this subject - please correct me when I over-simplify and feel very free to point me to new sources of information, particularly audiovisual ones.
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